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1.
Talanta ; 236: 122877, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635257

RESUMO

A covalent organic framework (named as TpDq) linked by ß-ketoamine was prepared by imine condensation reaction with 1,3,5-triformylphloroglucinol (TFP) and 2,6-diaminoanthraquinone (DAAQ) as building blocks. Via employing a functionalized modification strategy, a new lanthanide complex Eu3+-ß-diketone functionalized covalent organic framework hybrid material, Eu-TTA@TpDq (TTA = 2-thenoyltrifluoroacetone), has been synthesized. After post-synthetic modification (PSM), the shape and structure of the parent framework is well preserved and the modified material shows remarkable luminescence properties. Based on this, we designed it as a fluorescent probe and tried to use it to sense common aldehydes. The results indicate that Eu-TTA@TpDq exhibits a turn-off response toward glutaraldehyde which can distinguish from other common aldehydes. The fluorescent probe has the advantages of reusability, pH stability (4.50-8.52), fast luminescence response (<1 min) and low detection limit. The linear range of this method was 0-100 µM; the detection limit was 4.55 µM; the relative standard deviation was 2.16%. Furthermore, it has broad application prospect in both practical sensing of glutaraldehyde in water environment and simple detection of glutaraldehyde vapor. In addition, we preliminarily discussed the possible sensing mechanism.


Assuntos
Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Glutaral , Cetonas , Luminescência
2.
Biomater Sci ; 9(22): 7617-7635, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34671797

RESUMO

To conveniently and effectively cure heart valve diseases or defects, combined with transcatheter valve technology, bioprosthetic heart valves (BHVs) originated from the decellularized porcine pericardium (D-PP) have been broadly used in clinics. Unfortunately, most clinically available BHVs crosslinked with glutaraldehyde (GA) were challenged in their long-term tolerance, degenerative structural changes, and even failure, owing to the synergistic impact of multitudinous elements (cytotoxicity, calcification, immune responses, etc.). In this work, dialdehyde pectin (AP) was prepared by oxidizing the o-dihydroxy of pectin with sodium periodate. Hereafter, the AP-fixed PP model was obtained by crosslinking D-PP with AP with high aldehyde content (6.85 mmol g-1), for acquiring excellent mechanical properties and outstanding biocompatibility. To further improve the hemocompatibility of the AP-fixed PP, a natural and specific inhibitor of thrombin (hirudin) was introduced to achieve surface modification of the AP-fixed PP. The feasibility of crosslinking and functionalizing AP-fixed PP, which was a potential leaflet material of BHVs, was exhaustively and systematically evaluated. In vitro studies found that hirudin-loaded and AP-fixed PP (AP + Hirudin-PP) had synchronously achieved effective fixation of collagen, highly effective anticoagulation, and good HUVECs-cytocompatibility. In vivo results revealed that the AP + Hirudin-PP specimens recruited the minimum immune cells in the implantation experiment, and also presented an excellent anti-calcification effect. Overall, AP + Hirudin-PP was endowed with competitive collagen stability (compared with GA-fixed PP), excellent hemocompatibility, good HUVECs-cytocompatibility, low immunogenicity and outstanding anti-calcification, suggesting that AP + Hirudin-PP might be a promising alternative to GA-fixed PP and exhibited a bright prospect in the clinical applications of BHVs.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Animais , Anticoagulantes , Glutaral , Valvas Cardíacas , Hirudinas , Pectinas , Pericárdio , Suínos
3.
ScientificWorldJournal ; 2021: 9342748, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712107

RESUMO

Background: Recently, an outbreak of a novel human coronavirus SARS-CoV-2 has become a world health concern leading to severe respiratory tract infections in humans. Virus transmission occurs through person-to-person contact, respiratory droplets, and contaminated hands or surfaces. Accordingly, we aim at reviewing the literature on all information available about the persistence of coronaviruses, including human and animal coronaviruses, on inanimate surfaces and inactivation strategies with biocides employed for chemical and physical disinfection. Method: A comprehensive search was systematically conducted in main databases from 1998 to 2020 to identify various viral disinfectants associated with HCoV and methods for control and prevention of this newly emerged virus. Results: The analysis of 62 studies shows that human coronaviruses such as severe acute respiratory syndrome (SARS) coronavirus, Middle East respiratory syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV), canine coronavirus (CCV), transmissible gastroenteritis virus (TGEV), and mouse hepatitis virus (MHV) can be efficiently inactivated by physical and chemical disinfectants at different concentrations (70, 80, 85, and 95%) of 2-propanol (70 and 80%) in less than or equal to 60 s and 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Additionally, glutaraldehyde (0.5-2%), formaldehyde (0.7-1%), and povidone-iodine (0.1-0.75%) could readily inactivate coronaviruses. Moreover, dry heat at 56°C, ultraviolet light dose of 0.2 to 140 J/cm2, and gamma irradiation could effectively inactivate coronavirus. The WHO recommends the use of 0.1% sodium hypochlorite solution or an ethanol-based disinfectant with an ethanol concentration between 62% and 71%. Conclusion: The results of the present study can help researchers, policymakers, health decision makers, and people perceive and take the correct measures to control and prevent further transmission of COVID-19. Prevention and decontamination will be the main ways to stop the ongoing outbreak of COVID-19.


Assuntos
COVID-19/prevenção & controle , Desinfetantes/farmacologia , Desinfecção/instrumentação , SARS-CoV-2 , Inativação de Vírus/efeitos dos fármacos , 2-Propanol/farmacologia , Animais , COVID-19/virologia , Coronavirus Canino/efeitos dos fármacos , Desinfecção/métodos , Etanol/farmacologia , Formaldeído/farmacologia , Raios gama , Glutaral/farmacologia , Temperatura Alta , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Vírus da Hepatite Murina/efeitos dos fármacos , Povidona-Iodo/farmacologia , Vírus da SARS/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Vírus da Gastroenterite Transmissível/efeitos dos fármacos , Raios Ultravioleta
4.
Soft Matter ; 17(37): 8459-8464, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34494056

RESUMO

Exposure of lysine-containing peptide-based gelators to the cross-linking agent glutaraldehyde allows tuning of gel mechanical properties. The effect of cross-linking depends on the position of the lysine residue in the peptide chain, the concentration of gelator and the conditions under which cross-linking takes place. Through control of these factors, cross-linking leads to increased gel strength.


Assuntos
Hidrogéis , Lisina , Reagentes para Ligações Cruzadas , Glutaral , Peptídeos
5.
World J Microbiol Biotechnol ; 37(10): 174, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34519903

RESUMO

Microbiologically influenced corrosion (MIC) is one of the major corrosion threats in the oil and gas industry. It is caused by environmental biofilms. Glutaraldehyde is a popular green biocide for mitigating biofilms and MIC. This work investigated the efficacy of glutaraldehyde enhancement by food-grade green chemical D-limonene in the biofilm prevention and MIC mitigation using a mixed-culture oilfield biofilm consortium. After 7 days of incubation at 37 °C in enriched artificial seawater in 125 mL anaerobic vials, the 100 ppm (w/w) glutaraldehyde + 200 ppm D-limonene combination treatment reduced the sessile cell counts on C1018 carbon steel coupons by 2.1-log, 1.7-log, and 2.3-log for sulfate reducing bacteria, acid producing bacteria, and general heterotrophic bacteria, respectively in comparison with the untreated control. The treatment achieved 68% weight loss reduction and 78% pit depth reduction. The 100 ppm glutaraldehyde + 200 ppm D-limonene combination treatment was found more effective in biofilm prevention and MIC mitigation than glutaraldehyde and D-limonene used individually. Electrochemical tests corroborated weight loss and pit depth data trends.


Assuntos
Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Desinfetantes/farmacologia , Glutaral/farmacologia , Limoneno/farmacologia , Aço/química , Bactérias/crescimento & desenvolvimento , Corrosão , Campos de Petróleo e Gás , Água do Mar/microbiologia
6.
J Vis Exp ; (173)2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34338682

RESUMO

Chemical fixation has been used for observing the ultrastructure of cells and tissues. However, this method does not adequately preserve the ultrastructure of cells; artifacts and extraction of cell contents are usually observed. Rapid freezing is a better alternative for the preservation of cell structure. Sandwich freezing of living yeast or bacteria followed by freeze-substitution has been used for observing the exquisite natural ultrastructure of cells. Recently, sandwich freezing of glutaraldehyde-fixed cultured cells or human tissues has also been used to reveal the ultrastructure of cells and tissues. These studies have thus far been carried out with a handmade sandwich freezing device, and applications to studies in other laboratories have been limited. A new sandwich freezing device has recently been fabricated and is now commercially available. The present paper shows how to use the sandwich freezing device for rapid freezing of biological specimens, including bacteria, yeast, cultured cells, isolated cells, animal and human tissues, and viruses. Also shown is the preparation of specimens for ultrathin sectioning after rapid freezing and procedures for freeze-substitution, resin embedding, trimming of blocks, cutting of ultrathin sections, recovering of sections, staining, and covering of grids with support films.


Assuntos
Substituição ao Congelamento , Técnicas Histológicas , Animais , Congelamento , Glutaral , Humanos , Microscopia Eletrônica
7.
Braz J Cardiovasc Surg ; 36(3): 295-300, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387971

RESUMO

INTRODUCTION: This study aims to test the effect of phenytoin as an inhibitor of the process of dystrophic calcification in bovine pericardium and porcine leaflets implanted in the subcutaneous tissue of rats. METHODS: Isolated segments of biomaterials were implanted subcutaneously in young rats. The study groups received 500 mg phenytoin per kilogram of diet per day. After 90 days, samples were collected and quantitative calcification assessment by optical microscopy, radiological studies with mammography, and atomic emission spectrometry were performed. RESULTS: Inflammatory reaction was a frequent finding in all groups when analyzed by optical microscopy. The calcium level assessed by atomic absorption spectrophotometry was significantly lower in the study groups using phenytoin compared to the control groups (control bovine pericardium group X=0.254±0.280 µg/mg; study bovine pericardium group X=0.063±0.025 µg/mg; control porcine aortic leaflets group X=0.640±0.226 µg/mg; study porcine aortic leaflets group X=0.056±0.021 µg/mg; P<0.05). Radiologic studies revealed a statistically significant difference between the groups treated with and without phenytoin (not only regarding the bovine pericardium but also the porcine leaflets). CONCLUSION: The results obtained suggest that phenytoin reduces the calcification process of bovine pericardium segments and porcine aortic leaflets in subdermal implants in rats; also, the incidence of calcification in bovine pericardium grafts was similar to that of porcine aortic leaflets.


Assuntos
Bioprótese , Calcinose , Próteses Valvulares Cardíacas , Animais , Aorta , Calcinose/prevenção & controle , Bovinos , Glutaral , Pericárdio , Fenitoína/farmacologia , Ratos , Suínos
8.
Biomolecules ; 11(5)2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068806

RESUMO

Mitochondria are highly dynamic organelles, constantly undergoing shape changes, which are controlled by mitochondrial movement, fusion, and fission. Mitochondria play a pivotal role in various cellular processes under physiological and pathological conditions, including metabolism, superoxide generation, calcium homeostasis, and apoptosis. Abnormal mitochondrial morphology and mitochondrial protein expression are always closely related to the health status of cells. Analysis of mitochondrial morphology and mitochondrial protein expression in situ is widely used to reflect the abnormality of cell function in the chemical fixed sample. Paraformaldehyde (PFA), the most commonly used fixative in cellular immunostaining, still has disadvantages, including loss of antigenicity and disruption of morphology during fixation. We tested the effect of ethanol (ETHO), PFA, and glutaraldehyde (GA) fixation on cellular mitochondria. The results showed that 3% PFA and 1.5% GA (PFA-GA) combination reserved mitochondrial morphology better than them alone in situ in cells. Mitochondrial network and protein antigenicity were well maintained, indicated by preserved MitoTracker and mitochondrial immunostaining after PFA-GA fixation. Our results suggest that the PFA-GA combination is a valuable fixative for the study of mitochondria in situ.


Assuntos
Fixadores/farmacologia , Formaldeído/farmacologia , Glutaral/farmacologia , Mitocôndrias/ultraestrutura , Polímeros/farmacologia , Animais , Camundongos , Microscopia Confocal , Mitocôndrias/efeitos dos fármacos
9.
Enzyme Microb Technol ; 148: 109817, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116748

RESUMO

Papain was immobilized onto Ti3C2 MXene nanosheets by physical adsorption and physical adsorption combined with covalent crosslinking with glutaraldehyde. Ti3C2 MXene nanosheets were prepared by hydrofluoric acid etching method. The resulting products were well characterized by SEM, BET, XRD, FTIR, XPS. The optimized immobilization conditions are pH 6.5, immobilization time of 20 h, immobilization temperature of 10℃, and 10 mL 2 mg mL-1 papain, the amount of papain immobilized was 156 mg g-1, the activity of the immobilized papain determined was 1701 U∙g-1. The immobilized papain exhibited enhanced pH and temperature endurances, immobilized papain also showed improved storage stability (39.25 % and 65.57 % after 20 days of storage at 4 °C). papain reusability was significantly improved after immobilization and it retained more than 50 % of its initial activity after 5 repeated cycles. Interestingly, the results of immobilized enzymes demonstrated that the immobilization of enzymes on Ti3C2 MXene is feasible. Such approach could be transferred to other support systems for anchoring enzyme.


Assuntos
Papaína , Titânio , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Glutaral , Concentração de Íons de Hidrogênio , Temperatura
10.
J Mech Behav Biomed Mater ; 121: 104588, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34091153

RESUMO

A primary cause of bioprosthetic heart valve failure is premature degeneration of the pericardial leaflets, owing specifically to mechanical fatigue. There remains a paucity of experimental data and understanding of the fatigue-damage behaviour of this collagenous tissue under complex loading regimes. To meet this knowledge gap, a novel pressure inflation system was designed and built, to cyclically load circular samples of glutaraldehyde fixed bovine pericardium, under equibiaxial bulge conditions. A study up to 60 million cycles revealed new insights into the fatigue behaviour of pericardial tissue, where a statistically significantly higher level of permanent set was found in samples with high collagen fibre dispersion, in comparison to those with highly aligned fibres. Whilst permanent set is known to occur in the non-collagenous matrix of pericardium, this study demonstrates that at physiological loads, which elicit a matrix dominant mechanical response, permanent set and thus tissue-level damage, is still mediated by the underlying collagen fibres.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Animais , Bovinos , Glutaral , Valvas Cardíacas , Pericárdio
11.
J Zoo Wildl Med ; 52(2): 838-842, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130433

RESUMO

The reliability of packed cell volumes (PCV), total solids (TS), blood glucose (BG), γ-glutamyl transferase (GGT), and glutaraldehyde test in determining passive transfer of colostral immunoglobulins was investigated in nine species of cervids: axis deer (Axis axis), hog deer (Axis porcinus), sika deer (Cervus nippon), tufted deer (Elaphodus cephalophus), Père David's deer (Elaphurus davidianus), pudu (Pudu puda), sambar deer (Rusa unicolor), barasinga deer (Rucervus duvaucelli), and Eld's deer (Rucervus eldii). Individually the parameters evaluated were significant though imperfect predictors of passive transfer status in cervids. Interpreted collectively as a panel along with neonate condition, these tests were clinically helpful in diagnosing failure of passive transfer (FPT). Collectively interpreting test results as a panel along with clinical assessment of the animal is recommended. Some species-specific variations in TS, GGT, and glutaraldehyde test results were identified.


Assuntos
Cervos/imunologia , Imunidade Materno-Adquirida , Animais , Biomarcadores/sangue , Glicemia , Colostro/química , Feminino , Glutaral/sangue , gama-Glutamiltransferase/sangue
12.
Biomolecules ; 11(5)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947162

RESUMO

Nowadays, enzyme-mediated processes offer an eco-friendly and efficient alternative to the traditional multistep and environmentally harmful chemical processes. Herein we report the enzymatic synthesis of cladribine by a novel 2'-deoxyribosyltransferase (NDT)-based combined biocatalyst. To this end, Lactobacillus delbrueckii NDT (LdNDT) was successfully immobilized through a two-step immobilization methodology, including a covalent immobilization onto glutaraldehyde-activated biomimetic silica nanoparticles followed by biocatalyst entrapment in calcium alginate. The resulting immobilized derivative, SiGPEI 25000-LdNDT-Alg, displayed 98% retained activity and was shown to be active and stable in a broad range of pH (5-9) and temperature (30-60 °C), but also displayed an extremely high reusability (up to 2100 reuses without negligible loss of activity) in the enzymatic production of cladribine. Finally, as a proof of concept, SiGPEI 25000-LdNDT-Alg was successfully employed in the green production of cladribine at mg scale.


Assuntos
Cladribina/metabolismo , Lactobacillus delbrueckii/enzimologia , Transferases/química , Transferases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biocatálise , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glutaral/química , Química Verde , Concentração de Íons de Hidrogênio , Dióxido de Silício/química , Temperatura
13.
J Adv Res ; 30: 185-196, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34026295

RESUMO

Introduction: Chemotherapeutic drugs are the main intervention for cancer management, but many drawbacks impede their clinical applications. Nanoparticles as drug delivery systems (DDSs) offer much promise to solve these limitations. Objectives: A novel nanocarrier composed of red blood cell (RBC)-derived vesicles (RDVs) surface-linked with doxorubicin (Dox) using glutaraldehyde (glu) to form Dox-gluRDVs was investigated for improved cancer therapy. Methods: We investigated the in vivo antineoplastic performance of Dox-gluRDVs through intravenous (i.v.) administration in the mouse model bearing subcutaneous (s.c.) B16F10 tumor and examined the in vitro antitumor mechanism and efficacy in a panel of cancer cell lines. Results: Dox-gluRDVs can exert superior anticancer activity than free Dox in vitro and in vivo. Distinct from free Dox that is mainly located in the nucleus, but instead Dox-gluRDVs release and efficiently deliver the majority of their conjugated Dox into lysosomes. In vitro mechanism study reveals the critical role of lysosomal Dox accumulation-mediated mitochondrial ROS overproduction followed by the mitochondrial membrane potential loss and the activation of apoptotic signaling for superior anticancer activity of Dox-gluRDVs. Conclusion: This work demonstrates the great potential of RDVs to serve a biological DDS of Dox for systemic administration to improve conventional cancer chemotherapeutics.


Assuntos
Doxorrubicina/administração & dosagem , Eritrócitos/química , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Nanopartículas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Fixadores/química , Glutaral/química , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/uso terapêutico , Neoplasias/metabolismo , Espécies Reativas de Oxigênio
14.
Int J Biol Macromol ; 183: 1743-1752, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34051252

RESUMO

In this study, active antibacterial cross-linked composite films were prepared through incorporating ε-poly-l-lysine (ε-PLL) into Siberian sturgeon gelatin-chitosan mixture. Cross-linking was performed by Glutaraldehyde (G) and/or Cinnamaldehyde (C). The antimicrobial, ε-PLL release, mechanical and morphological properties were then investigated. The addition of G to the biopolymer mixture significantly resulted in lower water vapor permeability, enhanced mechanical strength, lower moisture content, and water solubility. The FTIR spectra indicated the formation of imine bonds in the composite film network. The microstructure of composite films was affected by the cross-linking agent. The films cross-linked by G and C showed smooth and rough surfaces, respectively. C induced very small pores in the cross-section of the composite film. The composite films incorporated with ε-PLL revealed higher and steady-state in vitro antimicrobial properties against food spoilage bacteria. A higher release of ε-PLL and hence higher antibacterial activity was measured in the matrices cross-linked by C than those cross-linked by G. The results showed that the ε-PLL-fortified fish gelatin/chitosan composite films can be considered as a food-packaging material. G and C, as cross-linkers, can improve the structural and antimicrobial properties of this composite film.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Gelatina/química , Polilisina/farmacologia , Acroleína/análogos & derivados , Acroleína/química , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Preparações de Ação Retardada , Escherichia coli/efeitos dos fármacos , Microbiologia de Alimentos , Embalagem de Alimentos , Glutaral/química , Permeabilidade , Polilisina/química , Salmonella typhimurium/efeitos dos fármacos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos
15.
J Biomater Sci Polym Ed ; 32(11): 1420-1449, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33941041

RESUMO

Mucoadhesive microspheres have their own significant amongst the various sustained release drug delivery systems. The prolonged residence time of these delivery devices at drug absorption site results in steep concentration gradient and enhanced bioavailability. In this study, the mucilage of Isabgol husk was applied as polymeric backbone to develop gliclazide loaded microspheres by crosslinking with glutaraldehyde. The formulations were studied for surface morphology, swelling behavior, particle size, in vitro release, release kinetics, in vitro mucoadhesion and gamma scintigraphy in rabbits. The release of gliclazide from microspheres was controlled by swelling of crosslinked microspheres followed by diffusion. Gamma scintigraphic images acquired for microspheres retention in gastrointestinal track of rabbits indicated the residence of formulation upto 24 h after oral administration. Gliclazide retained its integrity in polymeric matrix of microspheres as observed by Fourier transform infrared spectroscopy, differential scanning calorimetry and powder X-ray diffractometry. The sustained release of gliclazide and prolonged retention of microspheres in gastrointestinal track disclosed the rationality of mucoadhesive Isabgol husk microspheres in controlling the hyperglycemia in diabetes.


Assuntos
Gliclazida , Animais , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Glutaral , Microesferas , Tamanho da Partícula , Coelhos
16.
Acta Biomed ; 92(S1): e2021159, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33944842

RESUMO

Chemodectomas are rare neuroendocrine tumors that typically arise at the carotid bifurcation and progressively englobe the internal and external carotid artery. Surgical asportation of the capsulated mass is the elective treatment. Pre-procedural embolization of this high vascular tumors is highly recommended because it has shown to improve surgical outcome by reducing both, mean blood loss and total operation time. Many different embolization techniques have been described in literature. In the here presented case we opted for an endovascular approach using resorbable purified porcine skin gelatin cross-linked with glutaraldehyde microspheres (Optisphere - MEDTRONIC) as an embolic agent. These turned out to be very safe and effective in improving surgical outcome by reducing operative blood loss and thus reducing treatment-related morbidity.


Assuntos
Tumor do Corpo Carotídeo , Embolização Terapêutica , Animais , Tumor do Corpo Carotídeo/terapia , Gelatina , Glutaral , Suínos , Resultado do Tratamento
17.
Biosensors (Basel) ; 11(4)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921226

RESUMO

Electrochemical biosensing relies on electron transport on electrode surfaces. However, electrode inactivation and biofouling caused by a complex biological sample severely decrease the efficiency of electron transfer and the specificity of biosensing. Here, we designed a three-dimensional antifouling nano-biosensing interface to improve the efficiency of electron transfer by a layer of bovine serum albumin (BSA) and multi-walled carbon nanotubes (MWCNTs) cross-linked with glutaraldehyde (GA). The electrochemical properties of the BSA/MWCNTs/GA layer were investigated using both cyclic voltammetry and electrochemical impedance to demonstrate its high-efficiency antifouling nano-biosensing interface. The BSA/MWCNTs/GA layer kept 92% of the original signal in 1% BSA and 88% of that in unprocessed human serum after a 1-month exposure, respectively. Importantly, we functionalized the BSA/MWCNTs/GA layer with HbA1c antibody (anti-HbA1c) and 3-aminophenylboronic acid (APBA) for sensitive detection of glycated hemoglobin A (HbA1c). The label-free direct electrocatalytic oxidation of HbA1c was investigated by cyclic voltammetry (CV). The linear dynamic range of 2 to 15% of blood glycated hemoglobin A (HbA1c) in non-glycated hemoglobin (HbAo) was determined. The detection limit was 0.4%. This high degree of differentiation would facilitate a label-free POCT detection of HbA1c.


Assuntos
Técnicas Biossensoriais , Hemoglobina A Glicada/análise , Ácidos Borônicos , Impedância Elétrica , Glutaral , Humanos , Nanotubos de Carbono , Soroalbumina Bovina
18.
Bioessays ; 43(6): e2000312, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33857328

RESUMO

Biocidal agents such as formaldehyde and glutaraldehyde are able to inactivate several coronaviruses including SARS-CoV-2. In this article, an insight into one mechanism for the inactivation of these viruses by those two agents is presented, based on analysis of previous observations during electron microscopic examination of several members of the orthocoronavirinae subfamily, including the new virus SARS-CoV-2. This inactivation is proposed to occur through Schiff base reaction-induced conformational changes in the spike glycoprotein leading to its disruption or breakage, which can prevent binding of the virus to cellular receptors. Also, a new prophylactic and therapeutic measure against SARS-CoV-2 using acetoacetate is proposed, suggesting that it could similarly break the viral spike through Schiff base reaction with lysines of the spike protein. This measure needs to be confirmed experimentally before consideration. In addition, a new line of research is proposed to help find a broad-spectrum antivirus against several members of this subfamily.


Assuntos
Desinfetantes/farmacologia , Corpos Cetônicos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Antivirais/química , Antivirais/farmacologia , Desinfetantes/química , Formaldeído/química , Formaldeído/farmacologia , Glutaral/química , Glutaral/farmacologia , Humanos , Corpos Cetônicos/química , Corpos Cetônicos/metabolismo , Cetose/etiologia , Cetose/virologia , SARS-CoV-2/patogenicidade , Vírion/efeitos dos fármacos , Vírion/patogenicidade
19.
Int J Biol Macromol ; 182: 730-742, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33836191

RESUMO

The purpose of this study was to develop and characterize chitosan (Ch)-based films incorporated with varying molecular weight (Mw) and acetylation degree (AD) chitosan-depolymerization-products (CDP), to be applied as drug delivery materials. As compared to Ch-film, optical and antioxidant potentials of Ch/CDP-based films were improved, particularly using low Mw and AD-CDP. Whereas, films water resistance, mechanical and antibacterial properties increased as CDP-Mw increased and AD decreased. For the thermal and swelling behaviors, better values were obtained using higher Mw and AD-CDP. Further, to assess their in vitro ciprofloxacin (CFX)-release behavior, loaded-CFX Ch/CDP-based films, crosslinked using glutaraldehyde, were prepared. Expect of elongation at break, crosslinked CFX-loaded films showed increased optical, water resistance, tensile strength and thermal properties, as compared to unloaded films. The CFX-release profiles indicated that a slower and sustained release was observed, particularly when using lower Mw and AD-CDP, and mainly for the crosslinked films during 48 h. These films can release CFX for up to 54% in 6 and 24 h, at pH 1.2 and 7.4, respectively. Through this study, novel biodegradable, swellable and pH-sensitive crosslinked Ch/CDP-based films may be considered as suitable and promising drug delivery systems.


Assuntos
Antibacterianos/química , Antioxidantes/química , Quitosana/análogos & derivados , Portadores de Fármacos/química , Filmes Comestíveis , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Ciprofloxacina/administração & dosagem , Reagentes para Ligações Cruzadas/química , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Glutaral/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Resistência à Tração
20.
Ultrason Sonochem ; 74: 105551, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33894557

RESUMO

Chitosan nanoparticles (NPs) exhibit great potential in drug-controlled release systems. A controlled hydrodynamic cavitation (HC) technique was developed to intensify the emulsion crosslinking process for the synthesis of chitosan NPs. Experiments were performed using a circular venturi and under varying operating conditions, i.e., types of oil, addition mode of glutaraldehyde (Glu) solution, inlet pressure (Pin), and rheological properties of chitosan solution. Palm oil was more appropriate for use as the oil phase for the HC-intensified process than the other oil types. The addition mode of water-in-oil (W/O) emulsion containing Glu (with Span 80) was more favorable than the other modes for obtaining a narrow distribution of chitosan NPs. The minimum size of NPs with polydispersity index of 0.342 was 286.5 nm, and the maximum production yield (Py) could reach 47.26%. A positive correlation was found between the size of NPs and the droplet size of W/O emulsion containing chitosan at increasing Pin. Particle size, size distribution, and the formation of NPs were greatly dependent on the rheological properties of the chitosan solution. Fourier transform infrared spectroscopy (FTIR) analysis indicated that the molecular structure of palm oil was unaffected by HC-induced effects. Compared with ultrasonic horn, stirring-based, and conventional drop-by-drop processes, the application of HC to intensify the emulsion crosslinking process allowed the preparation of a finer and a narrower distribution of chitosan NPs in a more energy-efficient manner. The novel route developed in this work is a viable option for chitosan NP synthesis.


Assuntos
Quitosana/química , Hidrodinâmica , Nanopartículas/química , Nanotecnologia , Estudos de Viabilidade , Glutaral/química , Tamanho da Partícula , Reologia , Água/química
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